Jeff Lill is a popular man lately, as captain of the J.C. Widener, one of the state's few ice breakers.

After leaving its Annapolis harbor at 8:30 Wednesday morning, the Widener spent the day criss-crossing the waters off Anne Arundel County — beckoned for help from the creeks of the Severn River to government research buoys in the Chesapeake Bay. It cleared paths for a sea trial from an Annapolis marina, a waterman in search of rockfish on the South River, and a county fireboat in the West River's Parrish Creek.

"It would never have gotten out," Lill said of the fireboat, which luckily didn't have any emergencies to tend to. "They had ice 5 inches thick."

As this month's second blast of cold lingers, ice has collected on local bays, rivers and canals as it hasn't since perhaps the 1990s, said those whose livelihoods depend on the waterways. It is crimping seafood harvests, jacking up energy bills for marinas and prompting warnings for daredevils in ice skates.

Thawing is expected this weekend, but with nearly two months of winter left, there's no guarantee it will last. This month is expected to be among the ten coldest Januarys on record in Baltimore, and the nine days with single-digit lows recorded so far in Baltimore are the most for the month since 1982.

"I haven't worked for two weeks because of the ice," said Moochie Gilmer, a Kent Narrows waterman.

Another of the Maryland Department of Natural Resources' ice breakers, the A.V. Sandusky, cleared paths for dredging and construction in the waters east of Kent Island on Wednesday morning, but for Gilmer and his peers, it's too cold to make a difference.

"It freezes so quick at night now, it's probably not a big help unless you do have some open water somewhere to get to," Gilmer said. "Hopefully, next week when it starts to warm up, the more they break it up, the faster it will disappear."

The Chesapeake hasn't frozen over completely since the winter of 1977-1978, the fifth-coldest winter on record in Baltimore, because it occurs only after prolonged cold spells, said Jack Cover, general curator at the National Aquarium. He recalled skating on the Eastern Bay between Kent Island and the Eastern Shore while growing up, but that sort of ice coverage has been rare in recent years.

But with water temperatures falling to freezing and below, chunks of ice were covering as much as 70 percent of the waters the Widener traveled through Wednesday, said John Gallagher, director of hydrographic operations for the state Natural Resources Department. Ice sheets are thicker and larger on the Eastern Shore because of the cold northwesterly wind, keeping another state ship, the J.M. Tawes, busy clearing paths to and from Smith Island and Cambridge.

Snowfall can exacerbate icy conditions on the bay, not just because it's cold, but because it places a layer of fresh water atop the bay — water that freezes at closer to 32 degrees, rather than the 28 to 30 degrees needed to freeze brackish waters below and farther down the bay, Cover said.

The U.S. Coast Guard's cutters are also busy, keeping main commercial channels clear and rescuing boaters who have gotten trapped in the ice. In one case, a 30-foot sailboat that had ventured from Annapolis was trapped after drifting nearly to Poplar Island, close to Tilghman Island. Five people were rescued Tuesday from the boat, which was left behind to be towed at the owner's expense, said Jonathan Lindberg, a petty officer with the Coast Guard Sector Baltimore.

The 65-foot Coast Guard tugboat Chock is set to travel Thursday from its port in Baltimore to the Chesapeake and Delaware Canal across the upper Eastern Shore to survey ice conditions in the upper bay and the canal, Lindberg said. The Coast Guard also brought up another cutter, the Elm, from North Carolina to assist with ice-breaking efforts.

On Middle River, few recreational boaters are venturing out into waters where they could meet ice floes several inches thick — not to mention the frigid winds that have rarely relented this month. Marina owners use motorized fans beneath their piers to keep ice from freezing, circulating warmer waters that sit at the bottom, keeping pilings and any boats left in the water clear of ice.

"We've been struggling to keep it up," said Frank Bean, marina manager at the Chesapeake Yachting Center at the mouth of Frog Mortar Creek. "We have like 30 [fans] on every pier that we have. It's been a bear with this cold weather, and I hate to see the electric bill."

Ice on smaller bodies of water around the region has meanwhile proved enticing for ice skaters and hockey players, but parks officials caution that it may not be as sturdy as it was decades ago when freezes were more common. Baltimore County parks officials warned visitors to Robert E. Lee Park in North Baltimore that they would be cited for trespassing if found on Lake Roland.

"People have those kind of Norman Rockwell nostalgic views of skating," said Barry Williams, director of the county's parks department. "The reality is Norman Rockwell never did a picture of someone drowning."

Temperatures were forecast to rise above freezing for the first time in four days Friday, reaching the lower 40s, with highs pushing 50 degrees over the weekend. But cold, albeit more seasonable than recent stretches, was forecast to return Monday, with temperatures in the 30s and chances for more wintry precipitation.